Inkjet printers consume ink and, in many cases, solvent make-up. The ink and solvent make-up are typically supplied in disposable bottles. The bottles, and the printer in which the bottles are to be used, typically have mating features to allow fluids to be drawn from the bottles, and supplied into the printer.
Each ink bottle retains a finite amount of ink, typically a pint or liter of ink. As the inkjet printing system is used, the ink within the bottle is consumed. When the ink bottle is fully drained, the depleted ink bottle is removed and replaced with a new ink bottle.
In the course of replacing the ink bottle, excess ink may spill or leak. For example, when an operator grasps the ink bottle to replace it, the force applied may squeeze the ink bottle, thereby ejecting excess ink from the bottle. Ink spills produce a mess within the ink jet printing system, and possibly outside of the system e.g. on the surrounding flooring and on an operator, and are potentially a health and safety hazard.
Some manufacturers of inkjet printing systems provide ink bottles or solvent bottles with spring-loaded valves to prevent spillage when ink bottles are removed from, or added to, a printer. Typically the valve assembly is located within the consumables bottle and an additional capping feature is added externally to provide a permanent seal to the container, and prevent the sprung valve from being dislodged during transportation.
The consumable fluids of an inkjet system comprise or include volatile organic substances. When a sealed bottle is transported the bottle is not only subjected to a range of vibrations and shocks that could dislodge the spring-loaded valve but also, the consumables bottles may be subjected to a range of internal pressures caused by differences in vapour pressure arising from differing environmental temperatures found around the world. The external sealing bottle cap therefore needs to be robust and able to withstand pressures both higher and lower than atmospheric pressure. These changes in internal pressure tend to generate a force along the axis of the bottle and thus the cap must be particularly robust in that axis.
Additionally the cap of the bottle should not add significantly to the external dimensions of the container, and therefore to the volume of any secondary containers required by law for transportation of the bottle.
One existing form of transportation cap comprises a single piece of plastic that is snap-fitted onto the body of the container to form a permanent seal. The cap has a raised section, which is removed by a cutting action performed by a specially designed tool. The removal of the cap section by cutting is a potential hazard as it involves a sharpened edge that may also cut the user.
An alternative arrangement is the ring tab such as that found on many food containers. As is well known the tab, defined by a thinned line formed in the cap, is removed to open the container by pulling on a ring attached to the tab. This is not preferred for ink containers because a stronger joint is required than that which can be removed by a pulling action; and because of the additional volume occupied by the ring. Further, the jerking action which typically results when the tab is broken from the surrounding cap, can lead to spillage of the ink.
U.S. Pat. No. 5,222,530, International Patent Application 02/060808 and International Patent Application 2004/108584 all show forms of bottle cap in which a plug, integrally formed with the cap, is broken away from the remainder of the cap by a force applied along the axis of the bottle to which the cap is attached. This requires the cap to be weaker in the axial direction which, for the reasons stated above, is undesirable for the transport of inks. Further, breaking such plugs away from the remainder of the cap could easily lead to spillage.
An alternative form of frangible cap is shown in U.S. Pat. No. 4,355,729. The cap described in this patent is provided with a breakaway part having a prying bar under which the head of a screw driver may be located to pry the breakaway part from the remainder of the cap. Again the breakaway part is connected to the remainder of the cap by a joint which is particularly weak along the bottle axis and, again, the prying action could well lead to spillage upon the breakaway part detaching from the remainder of the cap.
It is an object of this invention to provide a method and/or apparatus which addresses the problems and considerations set forth above; or which at least offers a novel and useful alternative.